Division circuits are included in various arithmetic units and find widespread application. In division circuits, division is performed by inputting a dividend and a divisor and there is a possibility of overflowing of the quotient value of the division result.
An arithmetic unit is known which is designed to cope with such quotient value overflowing, which has a saturation operation function, and which, when the value of a quotient overflows, outputs a maximum value determined in advance in place of the value of the quotient obtained by the operation.
Before execution of division of a dividend by a divisor, determination as to whether or not the value of the quotient overflows can be made from the dividend and the divisor.
In the case of stepwise division executed by repeating an addition/subtraction step, however, there is a need to hold, in a storage circuit such as a register, till the completion of the stepwise division, information on a determination result obtained before execution of the division and indicating that the value of a quotient overflows.
In general, if information indicating that the value of a quotient overflows is held in a storage circuit such as a register, the circuit configuration of the division circuit is complicated and the circuit area is considerably increased.